A square is constructed using the hypotenuse line AC of right triangle ABC as a side, as shown below. Find the area of the square if AB = 5 and BC = 8.
Find the hypotenuse (which is the side length of the square) via the pythagorean theorem
a2 + b2 = c2
5^2 +8^2 = c^2 c = sqrt (89)
Area of square = side^2 sqrt(89)2 = 89 units 2